Classifications

• • C—CHEMISTRY; METALLURGY
  • C12—BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
  • C12P—FERMENTATION OR ENZYME-USING PROCESSES TO SYNTHESISE A DESIRED CHEMICAL COMPOUND OR COMPOSITION OR TO SEPARATE OPTICAL ISOMERS FROM A RACEMIC MIXTURE
  • C12P7/00—Preparation of oxygen-containing organic compounds
  • C12P7/40—Preparation of oxygen-containing organic compounds containing a carboxyl group including Peroxycarboxylic acids
  • C12P7/44—Polycarboxylic acids
  • C12P7/48—Tricarboxylic acids, e.g. citric acid
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10S435/00—Chemistry: molecular biology and microbiology
  • Y10S435/8215—Microorganisms
  • Y10S435/911—Microorganisms using fungi
  • Y10S435/921—Candida

Definitions

• This invention relates to a process for producing citric acid. More particularly, this invention relates to a process for producing citric acid by fermentation with a microorganism capable of producing citric acid belonging to Candida guilliermondii subsp. galactosa.
• citric acid by fermentation a method based on the use of mold fungi such as Aspergillus niger, etc., is well known, and recently a method based on the use of bacteria or yeasts has been reported.
• the method for producing citric acid by yeast reported by Tabuchi, Abe and others [Nihon Nogei Kagaku Kaishi 42,440 (1968); Nihon Nogei Kagaku Kai Koen Yoshi-shu, page 183 (1969)], is interesting by reason that in this method, the fermentation time is short, fermentation yield is high, and not only saccharine material, but also n-parafiin, etc. can be utilized as a carbon source.
• the strain used in the present invention is a variant of Candida gailliermondii.
• the preferred strain is Candida guilliermondii subsp. galactosa nov subsp. No. 610 (ATCC 20296).
• citric acid by fermentation with the present yeast in accordance with this invention, it is not necessary to control iron ion in the medium or add a special chemical thereto. Therefore, it is possible to use a relatively cheap raw fermentation material.
• the present yeast has a good hydrocarbon assin'iilability, therefore, such hydrocarbons as n-paraffin, and the like can be used as a carbon source in the fermentation process.
• the analysis on the enzymatic activities of the present yeast has revealed that the yeast has a remarkably higher isocitric acid dehydrogenase activity (the enzyme number 1.1.1.41) compared with other yeast. This activity is believed to enhance the productivity of citric acid.
• Patented Apr. 23, 1974 2265 ATCC 15585 is 3.20 10 u./mg. protein and that of the present yeast is 6.12X u./mg. protein.
• the present yeast was tested for microbiological characteristics and identified according to J. Lodder and N.J.W.
• the present yeast strain is identical with Candida guilliermondii and Candida gailliermondii var. membranaefaciens cited in The Yeasts, a Taxonomic Study except for the following characteristics:
• the present strain is capable of fermenting galactose at an ordinary rate
• the strain is negative in urease activity.
• the No. 610 strain readily forms a membrane when grown with ethanol, therefore, the strain was presumed to be akin to Canadida guilliermondii var. membranefaciens. However, in view of the above-mentioned differences or characteristics, the strain was identified to belong to a new subspecies of Candida guilliermondii, and the nef subspecies was names as Candida guilliermondii subsp. galactosa.
• Fermentation of the yeast strain of the present invention is conducted in an aqueous nutrient medium containing a carbon source which includes one or more carbonhydrates, hydrocarbons and/or other organic substances.
• the carbohydrates include various sugars and sugar alcohols; such as glucose, fructose, maltose, sucrose, molasses, starch, starch hydrolysate and the like.
• a single hydrocarbon or a mixture of various liquid, gaseous or solid hydrocarbons may be used as the main carbon source.
• Exemplary of these hydrocarbons are parafiins such as straight and branched chain hydrocarbons containing from 5 to 20 carbon atoms, and mixed hydrocarbons such as gas, oil, light oil, kerosene, crude oil and the like.
• the other suitable organic substances include alcohols such as glycerol, mannitol and sorbitol and organic acids, such as acetic acid.
• various organic and inorganic nitrogen compounds can be used such as ammonium, chloride, ammonium sulfate, ammonium nitrate, urea, peptone, yeast extract, meat extract, corn steep liquor, bouillon, fish meal, casein hydrolysates, etc.
• a nutrient factor such as vitamins, e.g. thiamine, biotin, pantothenic acid, etc.; amino acids, e.g. histidine, tyrosine, phenylalanine, threonine, leucine, cystine, etc.; or an organic nitrogen source containing the said substances.
• a trace of metal salt that is, iron sulfate, zinc sulfate, copper sulfate, molybdenate, calcium salt, or borate to the medium.
• Fermentation or culturing of the yeast strain is carried out under aerobic conditions, e.g. by aerobic shaking of the culture or by stirring and aeration of a submerged culture, at a temperature of about 20 to about 40 C., preferably at about 30 C.
• the fermentation proceeds at a pH of about 1.0 to about 9.0 and most favorabaly at a pH of about 6.0.
• pH regulators such as calcium carbonate, caustic soda, calcium hydroxide, ammonia or the like are added during the course of the culturing to maintain the desired pH level.
• citric acid may be recovered from the resulting culture liquor by various conventional techniques including ion exchange treatment, solvent extraction, precipitation, crystallization, centrifugation, adsorption, and the like.
• Candida guilliermondii subsp. galactosa No. 610 (ATCC 20296) cultured for 24 hours in a yeast bouillon medium was inoculated in the amount of 10% by volume into a 500-ml. Sakaguchi flask containing 50 ml. of an aqueous nutrient medium containing 8% molasses, 0.3% NH Cl, 0.05% KH PO 0.02% MgSO -7H O, and 4% CaCO and having a pH of 6.0, and cultured at 30 C. for 3 days with aerobic shaking (130 reciprocations per minute), whereby 41 mg./ml. of calcium citrate (calculated as citric acid) was formed at the end of fermentation.
• EXAMPLE 2 The same seed culture liquor of Candida guilliermomiii subsp. galactosa No. 610 (ATCC 20-296) as in Example 1 was inoculated into a 500 ml. Sakaguchi flask containing 50 ml. of an aqueous nutrient medium containing 3.3% (-v./v.) n-paraflin (a mixture of C12, C and C paraifins in equal volumes), 0.3% NH CI, 0.05% KH PO 0.02% MgSO -7H O, 0.001% FeSO -7H O, 500 /1. of MnSO -4I-I O, 500 7/1.
• EXAMPLE 3 The same seed culture liquor of Candida guilliermondii subsp. galactosa No. 610 (ATCC 20296) as in Example 1 was inoculated into a 500 ml. Sakaguchi flask containing 50 ml. of an aqueous nutrient medium containing 0.4% NH4C1, 0.05 KH PO 0.05 MgSO -7-H O, 0.1% yeast extract, 4% (v./v.) n-hexadecane, 0.01% CaCI -ZH O and 0.001% Bromocresol Green. Culturing was carried out at 28 C. for 8 days with aerobic shaking.
• a process for producing citric acid by fermentation which comprises culturing a citric acid-producing microorganism belonging to Candida guifliermondii subsp. galactosa No. 610 (ATCC 20296) in an aqueous nutrient medium containing a carbon source, and recovering citric acid from the resulting culture liquor.
• hydrocarbon is an equal mixture of C C and C normal parafiins.
• a process for producing citric acid which comprises culturing Candida guilliermondii subsp. galaotosa No. 610 (ATCC 20296) under aerobic conditions at temperatures of about 20 C. to about 40 C. and a pH of about 6 in an aqueous nutrient medium containing an alkaline pH regulator; accumulating a salt of citric acid in the resultant culture liquor and recovering citric acid therefrom.

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• Organic Chemistry (AREA)
• Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Zoology (AREA)
• Life Sciences & Earth Sciences (AREA)
• Wood Science & Technology (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Microbiology (AREA)
• General Chemical & Material Sciences (AREA)
• Biotechnology (AREA)
• Health & Medical Sciences (AREA)
• Biochemistry (AREA)
• Bioinformatics & Cheminformatics (AREA)
• General Engineering & Computer Science (AREA)
• General Health & Medical Sciences (AREA)
• Genetics & Genomics (AREA)
• Preparation Of Compounds By Using Micro-Organisms (AREA)
• Micro-Organisms Or Cultivation Processes Thereof (AREA)

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• 1971
  • 1971-11-09 GB GB5207571A patent/GB1366526A/en not_active Expired
  • 1971-11-09 US US00197149A patent/US3806414A/en not_active Expired - Lifetime
  • 1971-11-16 DE DE2156911A patent/DE2156911B2/de active Pending
  • 1971-11-16 CA CA127,822A patent/CA954463A/en not_active Expired
  • 1971-11-17 IT IT70761/71A patent/IT942871B/it active
  • 1971-11-17 FR FR7141100A patent/FR2115854A5/fr not_active Expired
  • 1971-11-17 NL NL7115848A patent/NL7115848A/xx unknown

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